![]() ![]() Hubble, ALMA and Webb are tag-teaming to assemble a holistic view of the debris disks around a number of stars. "So, you can see inner belts that we could never see before." "Where Webb really excels is that we're able to physically resolve the thermal glow from dust in those inner regions," said Schuyler Wolff, an assistant research professor at Steward and a co-author on the paper. The inner belts have been resolved for the first time by Webb in infrared light. However, none of them found any structure inside of it. Sharp images of the outermost belt around Fomalhaut have previously been taken by the Hubble Space Telescope, the Herschel Space Observatory and the Atacama Large Millimeter/submillimeter Array, or ALMA. ![]() Observations of their dust provide unique clues to the structure of an exoplanetary system, reaching down to Earth-sized planets and even asteroids, which are much too small to see individually. As small bodies like asteroids collide, their surfaces are pulverized into huge clouds of dust and other debris. Debris disks develop later, following the formation of planets and once the primordial gas has dispersed. The idea of a protoplanetary disk around a star goes back to the late 1700s when astronomers Immanuel Kant and Pierre-Simon Laplace independently developed the theory that the sun and planets formed from a rotating gas cloud that collapsed and flattened due to gravity. "By looking at the patterns in these rings, we can begin to make a little sketch of what a planetary system ought to look like – if we could actually take a deep enough picture to see the suspected planets." "I would describe Fomalhaut as the archetype of debris disks found elsewhere in our galaxy, because it has components similar to those we have in our own planetary system," said lead study author András Gáspár, an assistant astronomer at UArizona's Steward Observatory. NASA, ESA, CSA, András Gáspár/Steward Observatory, Alyssa Pagan/STScI ![]() The outer ring spans about 240 Earth-sun distances. The scale bar is labeled in astronomical units, which is the average distance between Earth and the sun, or 93 million miles. The "great dust cloud" is highlighted, and pullouts show it in two infrared wavelengths, 23 and 25.5 microns. This image shows the Fomalhaut system's features, including the inner and outer asteroid belts. But there has never been a view as spectacular – or as revealing – as Webb's. Astronomers first discovered Fomalhaut's disk in 1983. The dusty belts are the debris from collisions of larger bodies, similar to asteroids and comets, and are frequently described as debris disks. The belts encircle the young hot star, which is about 25 light-years from Earth and can be seen with the naked eye as the brightest star in the southern constellation Piscis Austrinus. The results are published in the journal Nature Astronomy. The inner belts in the Fomalhaut system – which had never been seen before – were revealed by Webb for the first time. The scale of the outermost belt is roughly twice the scale of our solar system's Kuiper belt, which consists of small bodies and cold dust beyond Neptune, the outermost known planet. There are three nested belts extending out to 14 billion miles, or 23 billion kilometers, from the star that's 150 times the distance of Earth from the sun. To the astronomers' surprise, the dusty structures are much more complex than the asteroid and Kuiper dust belts of our solar system. These belts most likely are carved by the gravitational forces produced by embedded, unseen planets. The image shows nested concentric rings of dust, some of which had never been seen before. This dust is organized into a second ring, indicating the presence of one or more planets nearby.Īdam Block and András Gáspár/Steward ObservatoryĪ team led by University of Arizona astronomers used NASA's James Webb Space Telescope to image the warm dust around a nearby young star, Fomalhaut, to study the first asteroid belt ever seen outside of our solar system in infrared light. JWST's MIRI instrument provides the full picture by revealing warm dust filling the inner part of the Fomalhaut system (orange). The resulting finer-grained particles, traced by the Hubble Space Telescope and shown here in blue, are blown out of the outer ring by the photons streaming from the star. ![]() Observations made with the Atacama Large Millimeter/Submillimeter Array reveal sand-sized grains orbiting the star, chipping away at each other (shown in red). This image shows how the components of the Fomalhaut debris system relate to each other. ![]()
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